This week, images in which FaceApp was used to turn frowns upside down were shared widely on Twitter. Kelly Grovier looks at why portrait painters of the past reserved a smile for the drunk, the dubious and the deranged.

“There is nothing more damning to go down to posterity”, Mark Twain insisted, “than a silly, foolish smile caught and fixed forever.” Though Twain was referring to expressions preserved in contemporary photographs, he could as easily have been describing the dominant attitude of artists up until the end of the 18th century. Before then, portraits were nothing to smile about.

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Though some ancient Greek sculptors are known to have plastered insipid grimaces (or what historians have dubbed “archaic smiles”) on the stony faces of their statues in order to demonstrate their skill in capturing the tension of facial muscles, an outright smile risked exposing the poor condition of teeth and gums prior to modern dentistry. They tended to be reserved for depicting the drunk, the dubious, and the deranged. Even as late as the Victorian Age (the era that coincided almost precisely with Twain’s life and career), one was far more likely to hear a photographer instruct his sitter to “say prunes” (a word that produces a tight Trump-like pout) than the chirpier “say cheese” (which forces the mouth into a broader Obama-like grin).

Notwithstanding the enigmatic smirks that complicate the lips of Leonardo Da Vinci’s Mona Lisa and Vermeer’s Girl with a Pearl Earring, wide toothy beams in the history of art are relatively hard to find. Until now. A series of snaps shared widely this week, created with the help of photo-manipulation technology (in the form of the recently released FaceApp), have transformed a clutch of dour museum countenances into a counterfactual history of human mirth.

Like a virtual vandal, Twitter user Olly Gibbs traipsed through the Rijksmuseum in Amsterdam “armed with Face App”, so he tweeted, “to brighten up a lot of the sombre looks on the paintings and sculptures”. Portrait after portrait, Gibbs’s joyful grinfitti transformed the moping mouths of old masters into a glib gallery of outrageous gaiety. With a simple snap (and the filter of an app), Gibbs wiped the sulks off the faces of glum courtiers and dismal noblewomen and even tickled the soulful brooding of a Rembrandt self-portrait into momentary jollity.

But the cumulative effect of so much enforced merriment is something less uplifting and more unnerving than one might expect. Such counterfeit fun is strangely sinister when painted with such a broad brush. Before long, the thin line between giddiness and the grotesque begins to blur as Gibbs’ intriguing subversions call to mind one of the more unsettling interventions in art history: Francis Bacon’s shocking reinvention in 1953 of Diego Velázquez’s Renaissance masterpiece, the Portrait of Pope Innocent X.

Long haunted by the penetrating stare of Velázquez’s portrait of the pontiff, the Irish-born Bacon (who obsessively hoarded reproductions of the painting, yet resisted ever visiting the original, which hangs in Rome’s Doria Pamphilj Gallery), transformed its intense regality into a mysterious cipher of psychological terror. Through the twisting lens of Bacon’s tortured psyche, the austere air of papal authority is melted into a visceral visage of howling horror. Rather than digitally extrapolating from a face’s contours how a smile might sculpt itself, as FaceApp does, Bacon’s mind merged the screaming mouth of a hysterical nurse in Sergei Eisenstein’s film Battleship Potemkin (another image that haunted him) with the tight lips of Velázquez’s inscrutable subject to produce an indelible icon of modernist angst. Placed alongside Gibbs’s FaceApp whimsy, Bacon’s dreadful totem reminds us that looking is just the first step in experiencing great art – that the eyes’s shutters are merely the first reflex in the complex transformation of seeing into feeling.

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